Soil improvement and change of living conditions in Ethopia
Soils are a fundamental natural resource and the basis for all life on land. Several environmental or anthropogenic influences can lead to a deterioration of the physical, chemical and biological conditions of soil quality, which is accompanied by a loss of the productive capacity of the soil and a serious depletion of soil biodiversity.
Arable soils in Ethiopia are among the oldest on the African continent. They have been severely eroded by the effects of water and wind erosion over the centuries, resulting in degradation and depletion of nutrients, with particular deficiencies in key nutrients such as N, P, K, S, and Zn. In this context, soil health and fertility play a crucial role in ensuring food security. The problems that most affect soil productivity in Ethiopia are waterlogging, soil acidification and alkalinity. As there is hardly any biomass recycling, the natural plant nutrient cycle has been interrupted due to human interventions. As a general practice, farmers remove all crops from fields and don’t use enough fertilizer to replenish the soil with organic matter and nutrients. As a result, grain yields are low, with a national average of less than 2 t/ha. However, most people in Ethiopia, about 80%, make their living from agriculture and livestock. Living conditions are correspondingly harsh for them. For daily food, girls and women often carry water and firewood many kilometers home, since there are no more resources close to their homes.
The difficulty of obtaining firewood and food has been exacerbated in recent years by environmental factors such as the El Niño weather phenomenon, locust plague and climate change. In addition, deforestation increased attached to transformation of woodland to pasture and arable land, which is associated with the background of the steadily growing population there. In the rural dwellings, food is prepared on simple, mostly open fires. Besides often occurring injuries to the cooks and children living in the house, it leads to harmful air quality, resulting in premature deaths due to respiratory, pulmonary, and cardiovascular diseases, among others.
An approach by the project, financed by the BMZ, is to improve living conditions in Ethiopia by introducing new technologies and processes for agricultural production and food processing (see graphic). The application of a combined organic fertilizer shall improve degraded farmland and elevate yields. In this process, biochar is mixed with digestate from biogas plants or compost material to form a biomass-based fertilizer for soil amendment. Incorporating the mixture into the soil increases water and nutrient holding capacities, and stimulates soil microbial biomass, soil fauna, and plant root growth, resulting in increased soil fertility and crop yield. Combined with a significant change in enzyme activities, there are biogeochemical effects on material cycles in the soil that simultaneously mitigate the effects of climate change
Apart from large-scale approaches, the biochar can also be produced locally by farmers using small scale pyrolysis units which can act as stoves as well. The introduction of improved stoves is already being implemented in many developing countries worldwide as a way to improve livelihoods. Currently available models allow more effective and low-emission cooking than the traditionally used 3-stone fire, meaning air pollution as well as required fuel amount is reduced. The essential focus of the introduction of improved stoves is the adaptation of the technology to local and cultural conditions. Materials that are locally and cheaply available should be used for manufacturing, and established traditions for food preparation should be considered. For example, a diet without the country's typical flatbread injera or traditionally prepared coffee is probably unthinkable in Ethiopia.
The approach to transform agriculture and food processing in Ethiopia will hopefully not only change the lives of a few people in Ethiopia, but will achieve real impact throughout a greater region. Since in this outlined way the farmers in Ethiopia can contribute to reduce net CO2 emission by sequestration through biochar production and its application for soil amendment. Via this minor advanced daily mode of life they can give a huge contribution to the reduction of greenhouse gas emissions.
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